The vacuum obtained for a whole reaction system is typically approximately 10-50 mbar, although even better vacuum can be achieved – we have observed around 3-5 mbar under stationary test conditions in Reactor-Ready.
The vacuum level that is obtained in a specific reaction system will depend on various factors, including:
- The type of reaction system – Reactor-Ready, Reactor-Ready Duo, Reactor-Ready Pilot and Lara have an advanced design with better sealing than other reaction systems, so particularly good vacuum can be achieved
- Whether glass cone stoppers (optional accessories) are used to plug any unused lid ports (required for the best possible vacuum), rather than Rodaviss sealing caps
- The particular vacuum pump used (considering the pump’s ultimate vacuum and speed etc.); also note that when a vacuum pump/tubing is new, you may need to run the vacuum for some hours before the best vacuum levels can be achieved
- Whether there is any water (or other substance) in the system – vacuum can cause this to evaporate, increasing the pressure
- The condition of all the seals/O-rings and piston – these are consumable parts and should be checked and replaced if required
- The condition and position of other components such as stirrer guide, stirrer shaft and probes
- Whether all joints are clean, assembled correctly and tight
- Whether all valves are closed properly
- Whether the vessel/lid clamp is tight enough
- Whether vacuum grease (silicone grease) is used on joints
- The stirring taking place (speed/viscosity etc.)
- The temperature within the vessel
- The reaction taking place within the vessel
For details of our vacuum testing procedure, please refer to our technical bulletin ‘TB 102 Reactor-Ready vacuum and pressure testing’, available to download here.